body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f4f4f4;
    display: flex;
    min-height: 100vh;
}

#wrapper {
    display: flex;
    flex: 1;
}

#sidebar {
    width: 250px;
    background-color: #333;
    color: #fff;
    display: flex;
    flex-direction: column;
    padding-top: 20px;
}

#content {
    flex: 1;
    padding: 20px;
    background-image: url('/img/20150123021039.jpg'); //固定壁纸
    /*background-image: url('https://www.dmoe.cc/random.php');//随机壁纸美女*/
    /*background-image: url('https://tu.ltyuanfang.cn/api/fengjing.php');//随机风景*/
    background-size: cover;
    background-position: center;
    color: #fff;
}

.nav-link {
    display: block;
    padding: 10px 20px;
    color: #fff;
    text-decoration: none;
    background-color: #555;
    margin-bottom: 5px;
    border-radius: 5px;
    transition: background-color 0.3s ease;
    text-align: center;
}

.nav-link:hover {
    background-color: #67ffd9;
}

.active {
    background-color: #4596af;
    text-align: center;
}

h1 {
    text-align: center;
    font-size: 30px;
    color: #000;
}

table {
    width: 100%; /* 让表格宽度占据父元素的100% */
    border-collapse: collapse;
}

td, th {
    padding: 8px;
    border: 1px solid #67ffd9;
}

@media only screen and (max-width: 600px) {
    /* 在窗口宽度小于等于600px时应用的样式 */
    #sidebar {
        width: 100%; /* 使侧边栏在小屏幕上占据100%宽度 */
    }

    #content {
        padding: 10px; /* 减小内容区域的内边距 */
    }
}
.download-btn {
    background-color: #3498db;
    border: none;
    color: white;
    padding: 15px 32px;
    text-align: center;
    text-decoration: none;
    display: inline-block;
    font-size: 16px;
    margin: 4px 2px;
    cursor: pointer;
    border-radius: 5px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.3);
    transition: all 0.3s ease;
}

.download-btn:hover {
    background-color: #2980b9;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.5);
}